I am almost flabbergasted by the spin and blunt-face upon which this news is delivered. We were just discussing the pot calling the kettle black with Apple / Adobe and now Microsoft have also come out in favour of a closed video format for an open web--IE9's HTML5 video support will allow H264 only. Update Now that the initial shock is over, I've rewritten the article to actually represent news rather than something on Twitter.

Nothing is compatible with QuickTime X, it doesn't have a plugin interface.

Amazing how I have no problems using flip4mac with QuickTime X.

They will block DirectShow codecs because they have said IE9 will use H264 _only_. Read the article.

It states:

IE9 will support playback of H.264 video only.

Which could mean support for h264 as so far as providing a CODEC but it doesn't rule out third parties providing a CODEC for other formats. Until more details are given about how exactly it is done - its all speculation. What ever the case maybe, though, h264 is a great format and it is good to see that Microsoft has embraced it for video playback instead of trying to push WMV or VC-1 as I would have expected in the past.